It is no different from previous versions of Windows. Just press PrtScr button and paste it into a program (paint, word, powerpoint, whatever you like). OR use the snipping tool (Cortana search: type snipping tool then click the snipping tool link). OR you can install a software program that does screenshots. I use SnagIt.

The easiest thing you can do is just press the "PrtScr" button on your keyboard.

If you want more flexibility, then there is a program on Win 10 called the "Snipping Tool" that you can run in the background, and you can use it take screenshots of only one window, or a rectangular area of the screen, less than the full screen, etc.

Windows 10 includes a Snipping Tool, that allows you to copy rectangular portions or entire screen and paste it into a picture edit program like Windows Paint, or if you download Photofiltre, or many more.
Laptop Keyboards at least have an FN key to access the Prtsc on END on most keyboards and that does copy the screen to clipboard.
Here is a complete instruction set of methods: https://www.howtogeek.com/226280/how-to-...

2. Use the keyboard shortcut: Windows + PrtScn. If you want to take a screenshot of the whole screen and save it as a file on the hard drive, without using any other tools, then press Windows + PrtScn on your keyboard. Windows stores the screenshot in the Pictures library, in the Screenshots folder.Apr 4, 2017